The length of time that your waterproof spray will last and remain effective depends on what type of spray you are using.
For example, typical footwear waterproofing spray will only last for four weeks, however if you are using a Durable Water Repellent (DWR) spray on a jacket or tent then it can last for years, with most DWRs remaining effective for over 100 washes.
Does Waterproof Spray Expire?
Waterproof sprays don’t expire, if you have a ten-year-old bottle laying around chances are it will still work absolutely fine.
The spray bottles do not have expiry dates on them because the spray is not designed to expire. However, once sprayed the waterproofing does have a limited lifespan so in this sense you could say that waterproof spray does expire.
Exposure to the weather causes waterproof sprays to break down over time and become less effective.
UV exposure from the sun can slowly degrade the spray and exposure to rain, over time will also assist in breaking it down.
Waterproof spray is often rubbed off by friction from your movement.
This is particularly true of shoes because they are in constant contact with the ground so they regularly get scuffed against dirt and debris which rubs off the spray.
Shoes therefore need waterproofing more frequently than other garments.
Also Read: Is Spray Paint Waterproof?
Waterproof Spray Uses & Types
The effectiveness and durability of waterproof sprays vary depending on the type of spray you use.
The purpose of waterproof spray is (obviously) to help a piece of fabric or a particular surface to repel water.
Typically waterproof spray is used on items including:
Items such as Jackets and Tents require a long-lasting waterproof spray. To waterproof these Durable Water Repellent sprays should be used.
If you are using your jacket pretty much every day then the spray should last at least 6 months before reapplication is necessary.
You don’t need to worry about washing the spray off as DWRs can easily survive over 100 washes providing you use a mild detergent.
Extra strong detergents can damage the spray leaving you with patchy spots which are less waterproof than they should be.
Strong detergents are sometimes used to try and break down the waterproof covering in an attempt to make it possible to dye waterproof fabric.
Don’t do it!
It doesn’t work, it just makes an ugly mess of your coat!
Providing you avoid using strong detergents then your fabric should remain waterproof for a long time.
If you only use your jacket irregularly, for example once every week or every couple of weeks when it is raining or when you go away on holiday then realistically you can expect the waterproof spray to be effective for up to three years before a reapplication is necessary.
Types Of Waterproof Spray
There are two different ways of applying waterproofing to fabric, the method needed will depend on which type you buy:
- Spray-On: Most waterproof sprays are standard spray-on, they are ideal for a wide range of surfaces including hard or soft shell clothing and tent.
To apply them you just spray them on and leave them to dry, the length of time required to fully dry can range from 20 minutes to 24 hours depending on the spray, some may also require second coats.
- Instant Spray-On: As the name suggests this type of spray instantly drys on application, you just spray it on and it dries and is ready to wear within seconds.
Generally, instant spray will not last as long as none-instant sprays.
It is less hard-wearing and most suited to quick on the go applications, for example, if you are camping and notice your tent is letting water through during the night so you need a quick repair between rainstorms then instant spray-on is a good solution.
However, in most cases spray that requires a good bit of drying time is a better choice as it is a more durable and longer-lasting solution.
Alternatives To Waterproof Spray That Last Longer
If you’re looking for an alternative to waterproof spray then you have a few options which should last longer.
1. Wash In & Soak
Wash & soak solutions are made in much the same way and of much the same ingredients as spray-on solutions, just the application method is different.
Because wash and soak permeate the entire fabric this is best used on hardshell clothing that has no interior lining as the waterproofing can damage or change the feel of the lining.
Because it completely permeates the whole fabric it lasts longer than waterproof spray does.
Wash in and soak waterproofing solutions can usually be applied either in a washing machine or with a 10-20 minute soak in a bucket.
Wax is a tried and tested way of waterproofing clothes that has been around for years and is still very much in vogue now with companies like Barbour being famous for their wax jackets.
Waxing clothing is a lot more time-consuming than using spray but it will give a much more durable waterproof finish.
If you want to waterproof your jeans or a jacket then here’s how you do it:
- Get some clothing wax
- Lightly heat the wax and the clothes you are going to apply it to using a hairdryer.
- Rub the wax onto the fabric
- Heat the fabric again and smooth it off with your hands to give it a nice finish
- Leave the clothing for 24 hours to dry and cure.
Check out this article for a more detailed explanation of how to do this.